6 Works

Shallow-marine carbonate cementation in Holocene segments of the calcifying green alga Halimeda

Thomas Mann , André Wizemann , Marleen Stuhr , Yannis Kappelamann , Alexander Janßen , Jamaluddin Jompa & Hildegard Westphal
Early-diagenetic cementation of tropical carbonates results from the combination of numerous physico-chemical and biological processes. In the marine phreatic environment it represents an essential mechanism for the development and stabilization of carbonate platforms. However, many early-diagenetic cements that developed in the marine phreatic environment are likely to become obliterated during later stages of meteoric or burial diagenesis. In this contribution, a petrographic microfacies analysis of Holocene Halimeda segments collected on a coral island in the...

Measurement of Diffuse Submarine Groundwater Discharge at intertidal puddles at the Königshafen - Sylt

Sebastian Janßen , Alexandra Nozik , Ulf Mallast & Nils Moosdorf
Coastal regions represent a transition between land and sea. From the hydro(geo)logical point of view freshwater and saltwater are coming together here. The groundwater discharge which discharges directly into the sea is called submarine groundwater discharge (SGD). At the regional scale, SGD is often measured indirectly based on tracers. At the local scale, SGD flux over time can be measured directly, e.g. using seepage meters. However, this method only represents the punctual source of discharge....

Unique islets in SE Asia: How Holocene climate and sea-level controlled growth of a coral reef island

Yannis Kappelmann, Hildegard Westphal, André Wizemann & Thomas Mann
Coral reef islands are unconsolidated landforms, composed of skeletal carbonate from surrounding reefs and related ecosystems. Facing the predicted rise of sea-level and a changing environment in the next decades, response of low-lying coral reef islands is of great scientific and public interest. To better estimate future behavior, it is necessary to know and classify the effects of past environmental changes on the sedimentary system. In SE Asia, sedimentological understanding of the development of these...

No warming in the eastern Gulf of Mexico since 1845 recorded by a Siderastrea siderea coral from Cuba

Marie Harbott , Henry C. Wu , Henning Kuhnert , Simone Kasemann , Anette Meixner , Carlos Jimenez , Patricia González-Díaz & Tim Rixen
Changes in the surface ocean pH and temperature caused by the uptake of anthropogenic CO2 are posing a threat to calcifying marine organisms. Recent studies have observed significant impacts on coral reef ecosystems with impaired carbonate skeletal growth and decreased calcification due to acidifying oceans. The current coverage of observations for the northwestern Cuban coastal waters provides an incomplete picture of natural climate variability over interannual to interdecadal timescales, showing the need for high resolution...

A multi-proxy SST and surface seawater carbonate chemistry reconstruction of the post-Industrial Revolution Southwest Pacific

Sara Todorovic , Henry C. Wu , Braddock K. Linsley , Henning Kuhnert , Albert Benthien , Klaus-Uwe Richter , Markus Raitzsch , Jelle Bijma & Delphine Dissard
Oceanic uptake of anthropogenic CO2 emissions induced global seawater pH decrease by 0.1 since the Industrial Revolution by altering ocean chemistry with the reduction of carbonate ion concentrations and the saturation states of aragonite. Massive tropical corals are ideal palaeoceanographic archives providing high-resolution records of the most recent few hundred years and offer a valuable extension to instrumental measurements. The South Pacific Convergence Zone (SPCZ), the largest persistent precipitation band in the Southern Hemisphere with...

Dynamic as always – Sedimentary evolution of a coral reef island from the Spermonde Archipelago, Indonesia

Yannis Kappelmann , Hildegard Westphal , Dominik Kneer , André Wizemann & Thomas Mann
Leibniz Centre for Tropical Marine Research (ZMT), Fahrenheitstraße 6, Bremen, Germany(1);University of Bremen, Bibliothekstraße 1, Bremen, Germany(2);Bioplan GmbH, Strandstraße 32a, 18211 Ostseebad Nienhagen, Germany(3);Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Stilleweg 2, Hannover, Germany(4);The effects of changing climate and environmental conditions on coral reef islands have received a lot of attention, and the findings are discussed broadly. The low elevation of such islands above mean sea level and the largely unconsolidated sediment is exposing them to...

Registration Year

  • 2022

Resource Types

  • Text


  • Leibniz Centre for Tropical Marine Research
  • University of Bremen
  • Federal Institute for Geosciences and Natural Resources
  • Helmholtz Centre for Environmental Research
  • Hasanuddin University
  • Universität Hamburg
  • Interuniversity Institute for Marine Sciences in Eilat
  • Leibniz Centre for Tropical Marine Research (ZMT)
  • Cyprus Institute
  • Lamont-Doherty Earth Observatory